bugfixes and small features

Fixed config switches not registering the correct current value
Added better ux when image uploads are disabled
Fixed an issue where uploaded files were not being handled correctly
Added the ability to disable user registrations
Fixed some variables being unintendedly protected

app/views/user_cp/settings.html

@@ -3,7 +3,7 @@
     <hr>
     <div class="row justify-content-center">
         <div class="col-md-6">
-            <form action="" method="post" class="">
+            <form action="" method="post" class="" enctype="multipart/form-data">
                 <fieldset>
                     {PREFERENCES_FORM}
                 </fieldset>